This invention relates to devices for increasing and deflecting the thrust of a jet-propulsion engine of vertical or short takeoff and landing (hereinafter referred to as V/STOL) aircraft. More particularly, the invention concerns a thrust increasing and deflecting device for V/STOL aircraft, which device is capable of increasing and, moreover, deflecting the thrust at takeoff or landing of a jet-propulsion engine of a V/STOL aircraft by utilizing the jet reaction.
In general, a V/STOL aircraft is known to possess the double capacity of performing as a VTOL aircraft making possible vertical takeoff and landing and also as a STOL aircraft making possible takeoff and landing with short runway distances. For this purpose, a V/STOL aircraft is provided with means for changing the direction of the engine thrust during the transition flight from takeoff to forward or cruising flight and from forward flight to landing. In a V/STOL aircraft of this character in which the engine thrust used for cruising is utilized as lift force also in takeoff and landing in this manner, a mechanism for deflecting this thrust direction becomes necessary.
In a common conventional thrust deflecting device, a deflector comprising a plurality of panels which can be positionally adjusted is installed to the rear of a jet-propulsion engine and is capable of deflecting the jet flow discharged from the engine to a substantially perpendicularly downward direction.
In a known thrust deflecting device of this character, a loss in the thrust occurs when the jet flow is deflected which gives rise to a drop in the takeoff and landing performance. Furthermore, since the wall inner surface of the deflector is exposed to a jet flow at a high temperature, the panels of the deflector must be constructed of expensive heat-resistant material. Still another problem in the conventional thrust deflecting device has been that, in some instances, the installation of a cooling system has been necessary, which has increased the production cost as well as the weight.